text: Dr Nguyen Tri Dung, director of the HCMC Center for Disease Control (HCDC), said analysis of clinical factors and test results suggested that the person may be newly infected, with a currently unknown source of transmission?
classes:  No, the biggest concern about this suspected case is that the source of the infection is unknown as earlier, the man who was randomly sampled received a negative result.  Also, the biggest concern about this suspected case is that the source of the infection is unknown as earlier, the man who was randomly sampled received a negative result.  Yes, the biggest concern about this suspected case is that the source of the infection is unknown as earlier, the man who was randomly sampled received a negative result.